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Consistent Expression (consistent + expression)
Selected AbstractsExpression of Pax258 in the gastropod statocyst: insights into the antiquity of metazoan geosensory organsEVOLUTION AND DEVELOPMENT, Issue 6 2003Elizabeth K. O'brien Summary Most animals have sensory systems that allow them to balance and orient relative to the pull of gravity. Structures responsible for these functions range from very simple statocysts found in many aquatic invertebrates to the complex inner ear of mammals. Previous studies suggest that the specialized mechanosensory structures responsible for balance in vertebrates and insects may be homologous based on the requirement and expression of group II Pax genes (i.e., Pax-2/5/8 genes). Here we report the expression of a Pax-258 gene in the statocysts and other chemosensory and mechanosensory cells during the development of the gastropod mollusk Haliotis asinina, a member of the Lophotrochozoa. Based on the phylogenetic distribution of geo-sensory systems and the consistent expression of Pax-258 in the cells that form these systems, we propose that Pax-258, along with POU-III and -IV genes, has an ancient and conserved role in the formation of structures responsible for balance and geotaxis in eumetazoans. [source] Environmental and Genotypic Effects on Pod Characteristics Related to Common Bean QualityJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 4 2004Dr A. M. De Ron Abstract A collection of 121 common bean (Phaseolus vulgaris L.) landraces from Spain and Portugal (Iberian Peninsula) was evaluated in six environments (three locations and 2 years). Significant differences among landraces were found for period of flowering, pod maturity and pod morphology (weight, length, width/thickness and curvature). Wide variation among landraces was revealed by the range of variation observed. Environmental effects were not significant although year × location and landrace × year × location interactions were significant for all traits studied except for pod curvature. Poor consistent expression across the different environments for most of the traits studied was expressed by the low values of constancy (C) with the exception of width/thickness indicating that pod shape (round or flat) was expressed regularly across different environments. Principal component analysis enhanced differences among environments affecting the performance of the bean landraces evaluated. Analysis by environment showed that 51 landraces were adapted to specific environments and only four of them had broad geographical adaptability with similar performance under different conditions. These results could be a starting point for selection of new inbred lines adapted to distinct environments with potential for the improvement of current snap bean cultivars. [source] Stage-dependent Dishevelled-1 expression during mouse spermatogenesis suggests a role in regulating spermatid morphological changesMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 6 2006Pengpeng Ma Abstract Dishevelled (Dsh in Drosophila or DVL in mice) is a member of the highly conserved Wg/Wnt signaling pathway, which regulates important processes such as cell proliferation, polarity, and specification of cell fate. Three orthologous genes of Dishevelled (Dvl-1, Dvl-2, and Dvl-3) have been found in both humans and mice. They play pivotal roles in regulating cell morphology and a variety of changes in cell behaviors. In the present study, we show that the expression of Dvl-1 is stage-dependent during mouse spermatogenesis, although Dvl-2 and Dvl-3 show relative consistent expression. The expression of Dvl-1 mRNA first appears in pachytene spermatocytes, increases in round and elongating spermatids, and then turns to an undetectable level in mature sperm cells. Analyses of immunohistochemistry and immunofluorescence staining show that DVL-1 is present diffusely in the cytoplasm of pachytene spermatocytes and exhibits mainly a vesicular pattern and perinuclear distribution and a weak diffusely cytoplasmic signal in round and elongating spermatids. The vesicular pattern of DVL-1 has been observed by previous studies in somatic cells, and suggested to play roles in signal transduction. Immunoprecipitation experiments show that DVL-1 coimmunprecipitates with spermatogenic cells ,-actin rather than ,-tubulin. These results indicate that DVL-1 may be involved in spermatid morphological changes during mouse spermiogenesis through mediating signal transduction and/or regulating actin cytoskeleton organization. Mol. Reprod. Dev. © 2006 Wiley-Liss, Inc. [source] Clinical and biological significance of CXCL12 and CXCR4 expression in adult testes and germ cell tumours of adults and adolescents,THE JOURNAL OF PATHOLOGY, Issue 1 2009DC Gilbert Abstract Interaction between the chemokine CXCL12 (SDF1) and the G-protein coupled receptor CXCR4 is responsible for the maintenance of adult stem cell niches and is known to play an important role in utero in the migration of primordial germ cells. We demonstrate expression of CXCL12 by Sertoli cells and confirm CXCR4 expression by the germ cell population of the adult human testes. CXCR4 is also known to mediate organ-specific patterns of metastases in a range of common cancers. We identify consistent expression of CXCR4 mRNA and protein in testicular germ cell tumours (TGCT) that accounts for their patterns of relapse in sites of known CXCL12 expression. Extragonadal primary germ cell tumours express CXCR4 and their sites of occurrence are coincident with areas of known CXCL12 expression in utero. We show that CXCL12 stimulates the invasive migration of a TGCT cell line in vitro in a CXCR4-dependent fashion and activates ERK. Furthermore, we demonstrate that expression of CXCL12 in stage I non-seminomas is significantly associated with organ-confined disease post-orchidectomy and reduced risk of relapse (p = 0.003). This may be through the loss of CXCL12 gradients that might otherwise attract cells away from the primary tumour. We propose CXCL12 expression as a potential predictor of subsequent relapse that could lead to avoiding unnecessary treatment and associated late toxicities. Our observations support a role for CXCL12/CXCR4 in the adult germ cell population and demonstrate pathological function in germ cell tumour development and metastasis that may have clinical utility. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] | ||||||||||